ACF not visible in dedicated server

Have a linux box with gmod server. added ACF to addons on the server with folder structure as addons\ACF\lua so that should be correct. cloned with git. ran server and didn’t see any errors and it did say adding ACF or such. did exactly the same on my client PC. but if I join the server, ACF is not working, just cannot see it under tools or any sign of it. However, if i create a single player game on that client PC then ACF shows up no problem? I notice that the Armoured Combat Framework branch I am using from here does not have addon.txt - could this be the culprit? if that’s not the prime source for ACF then what is? the master old one here ?

I didn’t think ACF was linux compatible?

is it not? you can run dedicated server on linux so i would have thought addons work on whatever platform the game works…